A Contrastive Analysis Of Modality In Public Service Advertising And Commercial Advertising

In contemporary society, advertisements can be seen everywhere, which play animportant role in our life. Generally speaking, according to whether the purpose isprofit-oriented or not, advertising can be classified into two categories: public serviceadvertising (PSA) and commercial advertising (CA). As a unique discourse, the advertisingdiscourse has been studied from different angles, including semiotics, sociology, cognitivelinguistics, systemic functional linguistics(SFL) and so on.According to SFL, there are three meta-functions in the language system, namelyideational function, interpersonal function and textual function. And modality is one of theimportant means to realize the interpersonal function. In recent years, some scholars havestudied the advertising discourse in modality, but most of these studies just analyze thecommercial advertising or public service advertising respectively. The contrastive studies ofcommercial advertising and public service advertising have not attracted much attention.Therefore, based on the theoretical framework of modality theory in Halliday’s SystemicFunctional Grammar, this thesis intends to make a comparative analysis of modality in50PSA and50CA collected from TIME. It mainly analyzes the PSA and CA from three aspects,that is types of modality, modal orientations and modal values. Through the comparativeanalysis, the author tries to find are there any differences in these three aspects between thetwo types of ads.The research shows that there are not many modal expressions in PSA and CA. Butrelatively speaking, the modal resources in CA are more abundant than in PSA. In terms ofthe types of modality, there are significant differences in the frequency of probability andusuality, while there are no significant differences in obligation and inclination. In the modalorientations, there is a significant difference in subjective implicit orientation, while there areno significant differences in the frequency of subjective explicit orientation, objective explicitorientation and objective implicit orientation. As for the modal values, there is a significantdifference in low value, while there are no significant differences in the frequency of medianvalue and high value.Through the comparative analysis of the modality system in PSA and CA, the author hopes that it can help people better understand PSA and CA, make people clear about thesimilarities and differences of the the distribution of modality in PSA and CA and thedifferent influences of various modal expressions on the advertising discourse, and thuspromote further research of advertising discourse.